The present invention relates generally to door security devices which allow locking of the door in a fully closed position and a partially open position. The invention has specific application to the field of protection from home invasion and forced entry of any premises or building.
Residential security is an unfortunate but necessary part of owning or renting a home. Security of a commercial premises is also essential. Most premises are equipped with standard type door locks, dead-bolts and latches, which are effective when the door is closed, but it is frequently desirable to allow the door to open partially to talk to visitors. Opening the door subjects the occupants to an increased threat of home invasion or forced entry. Typical devices, such as door chains, designed to permit partial opening of the door, are inherently weak. The mounting of the chain and its components to the door frame and the door itself may be broken or torn from the their attachments. As such, there is a need in the market for door security devices that permit partial opening of the door without compromising security.
Many prior art devices have been developed which purport to solve this problem. However, none of the devices have been commercially successful because each of them has innate disadvantages that make them unattractive, non-functional or merely ineffective. The following represents a short discussion of the prior art inventions and the weaknesses thereof.
U.S. Pat. No. 3,690,709 (hereinafter referred to as ""709) is a cable based locking system. The cables attach to specialized hinges and are disposed so as to extend from each hinge angularly across the interior surface of the door to the bottom handle side corner. At the bottom handle side corner of the door, the cables are engaged via an offset flange to a rotating pivot bolt which is secured to the floor and/or the wall. The ""709 invention lacks visual appeal. People who have an interest in the aesthetic appeal of their homes or commercial establishments are unlikely to purchase an invention such as this, which requires the permanent fixture of cables covering most of the door""s interior surface. In addition, the cables are bulky and may reduce the functionality of the door as they take up a considerable amount of room. The device also puts a relatively large amount of torque and shear force on the pivot bolt. The offset flange, required by this invention to permit partial door opening, has the effect of laterally displacing the device""s bracing elements (the pivot bolt and its housing) away from the edge of the door. However, any force exerted to open the door is still exerted at the door""s edge and causes a torque on the pivot bolt which is proportional to the length of the offset flange and the force itself. Finally, the device requires the purchase specialty hinges, which add to the expense of the invention and to the complexity of installation.
U.S. Pat. No. 4,601,502 (hereinafter referred to as ""502) is a recessed floor plug with a spring loaded lock bar, which, when engaged, extends upwards from the floor plug, so as to block the path of the door. When not engaged, the lock bar retracts into the floor so that it is not intrusive. The lock bar is engaged by exerting downward pressure on the top of the bar, which depresses the bar below the floor surface and activates a spring release mechanism. One disadvantage of the ""502 invention is its arrangement in the floor. Because the invention has a relatively large number of moving parts, all housed in the recessive floor plug, dirt, dust and other contaminants (which accumulate naturally in doorways) can interfere with the device performance. The concentric arrangement of the lock bar within the floor plug is an entirely vertically oriented apparatus. Consequently, the device has little horizontal bracing, making it weaker when acting against horizontal forces tending to open the door. An additional consequence of the concentric arrangement is that the lock bar can only be as long as the depth of the floor plug. A large force acting against the upper part of the door can cause the door itself to break over the relatively short lock bar. Finally, the activation mechanism of the invention is difficult to operate. If the activation mechanism requires depression well below the floor, then a person may need to bend to floor level and use their hands; conversely, if the activation mechanism requires only minimal depression, then a person or household pet may accidentally activate the device by walking on it.
U.S. Pat. No. 5,040,835 (hereinafter referred to as ""835) comprises an angularly disposed rod, one end of which fits into an angular floor plug. The other end of the rod is inserted into a door mounted keeper and is vertically slideable therein, such that when the door is opened slightly, the rod slides vertically in the keeper and the rod angle changes. The disadvantages of the ""835 invention include the relatively large amount of space that the angularly disposed rod occupies in the entranceway of the premises. The floor plug of the device is also difficult to install, because it must be drilled at an angle and in precisely the correct location to permit the rod to translate properly within the keeper. In addition, the floor plug must be bored sufficiently wide to accommodate both different angular orientations of the rod. The extra room in the plug introduces play in the device and permits torque to act against the rod about the floor axis, such that an intruder may agitate the device, potentially bending or breaking it. Agitation, in turn, may cause the rod to slide within the keeper, allowing the door to partially open in undesirable situations and permitting extra torque to be applied to the rod.
U.S. Pat. No. 5,454,143 (hereinafter referred to as ""143) consists of a horizontal brace, which is slideably and rotatably inserted into a floor plug. When the door opens against the device, it rotates in the floor plug until the horizontal brace is in planar contact with the door. The ""143 invention has no locking mechanism, so an intruder may reach around a door that is slightly open with an arm or possibly a long instrument and unfasten the device. For this reason, the device is ordinarily disposed at the hinge side of the door. However, when the brace is located at the hinge side of the door, it does not provide as much torque to counteract the opening of the door. The invention also discloses a xe2x80x9cdispersion platexe2x80x9d mounted onto the door, which is claimed to protect the door from damage caused by the brace. The dispersion plate will not do much to disperse the force as the invention claims, because the dispersion plate shown in the disclosure is not much larger than the horizontal brace itself. The ""143 invention also suffers from the drawback that there is no effective place to store the bracing device when it is not in use. The bracing device must be detached from the door and may be hung on a hook. This requires the person to bend approximately to ground level to activate or deactivate the lock. In addition, the ""143 invention does not disclose a mechanism of locking the door in its closed position.
U.S. Pat. No. 5,531,490 (hereinafter referred to as ""490) discloses an xe2x80x9cS-shapedxe2x80x9d pivot bar, one end of which is inserted into a floor plug while the other end is allowed to translate horizontally within a brace on the interior surface of the floor. As one end of the pivot bar translates along the interior surface of the door, the pivot bar rotates and the door is allowed to open slightly. The major disadvantage with the ""490 invention is that it requires extensive modification to the door to provide a gap thereunder. The gap is required to allow the horizontal cross-piece of the pivot bar to rotate under the door. Not only does this gap involve extensive installation procedures and expense, it also permits an intruder to extend an elongated instrument under the door to cut or disengage the pivot bar. Additionally, a resident must bend nearly to floor level to activate or deactivate the device. Finally, the pivot bar does not extend very high onto the door. An intruder can exert force on the upper portion of the door which may break or significantly damage the door, and allow an intruder to force their way in.
In light of the above mentioned disadvantages with the prior art door security devices, it is an object of this invention to disclose a door security device which is aesthetically pleasing, does not occupy a large amount of space, is easy for a person to operate (without having to bend over), has a minimum number of working parts, and is sufficiently strong and functional to prevent forced entry without causing extensive damage to the door itself.
The invention herein disclosed relates to a door security apparatus which is particularly adapted to protect premises or buildings from forced entry and residences from home invasion. The apparatus comprises a hollow elongated housing which can be mounted vertically on an interior surface of a door and has a lower end which is spaced slightly from the floor of the premises. An elongated principal brace bar fits slideably and rotatably into the housing and has a vertical orientation, which is coaxial to the housing. The principal brace bar also has a lower end, which extends out of the bottom of the housing, but requires a small amount of clearance from the floor.
The device further comprises at least one substantially horizontal rod, which has a proximate end rigidly mounted to the lower end of the principal brace bar and a distal end, which extends in a horizontal fashion towards the inside of the premises. The horizontal rod fits through a vertically oriented, slideable brace bar, which has a hole in its body, corresponding to the horizontal rod. The slideable brace bar is mounted on the horizontal rod, in such a manner that the rod slides back and forth through the hole as the door moves back and forth from partially open to closed positions. In its active position, the lower end of the slideable brace bar extends below the surface of the floor.
Finally, the apparatus includes a receptacle in the floor, which receives the lower end of the slideable brace bar and immobilizes the slideable brace bar at the predetermined position of the receptacle. In this manner, when the door is opening, the horizontal rod slides towards the interior of the premises through the hole in the slideable brace bar. Eventually, the door reaches a position where the proximate end of the horizontal rod reaches the slideable brace bar and the slideable brace bar abuts against the principal vertical brace bar. Since the slideable brace bar is immobilized, the door is braced in this partially open position. On the other hand, when the door is closing, the horizontal rod slides backwards through the hole in the slideable brace bar. Eventually, the door will come to a rest in a fully closed position when the slideable brace bar is near the distal end of the horizontal rod.
Advantageously, the apparatus may further comprise a hole on the upper portion of the housing and a handle, protruding through the hole, which is attached to the upper portion of the principal brace bar. The handle may then be lifted to an elevated position, raising the slideable brace bar and disengaging it from the receptacle in the floor. With the slideable brace bar disengaged, the door may swing freely to and from a fully open position without impediment. By lowering the handle back to an active position, a resident may lower the slideable brace bar back into the receptacle, thereby reducing the door""s range of travel to positions between the fully closed position and the partially open position.
Preferably, the device may further comprise a locking mechanism which can secure the handle in the elevated position, or in the active position, such that the slideable brace bar may be locked in the in the disengaged position or locked in the floor receptacle. The locking mechanism may be implemented using a threaded member, which is tightenable against the housing or against a back plate mounted to the housing in a vicinity of the aperture.
Advantageously, the apparatus may include a second receptacle in the floor. The second receptacle is also dimensioned to receive the lower end of the slideable brace bar, but it is positioned adjacent to the interior surface of the closed door. If the slideable brace bar is inserted into this receptacle, then it will be immobilized immediately adjacent to the closed door and will brace the door in a fully closed position.
Advantageously, there may be a plurality of horizontal brace bars. There may also be a vertically oriented stopping column affixed to the distal end of the substantially horizontal rod. Such a stopping column may be operative to prevent the slideable brace bar from becoming disengaged from the substantially horizontal rod.
Preferably, there may be magnets on the elongated principal brace bar, the slideable brace bar, or the vertically oriented stopping column, which may be operative to gently affix the slideable brace bar at the proximate and/or distal ends of the substantially horizontal rod.
To improve the appearance of the device, the housing may be made of brass.
Advantageously, the handle of the device may be rotated such that the substantially horizontal rod can be rotated to a position that is substantially co-planar with the door.
To reduce the amount of material required, the housing may be a plurality of brackets mounted to the door.
To allow operation of the device from a remote location, there may be an electric motor attached to either the principal brace bar or the handle, and a remote control device which controls the electric motor to lower and raise the principle brace bar.
Another aspect of this invention concerns a door security apparatus adapted to protect a premises or building from forced entry and home invasion. The apparatus comprises a substantially hollow, elongated housing and an elongated principal brace bar, which is disposed so as to slideably and rotatably insert into the housing. The principal brace bar is coaxial to the housing and has an exterior end, which extends out of the housing at one end thereof. The apparatus also has at least one substantially perpendicular rod. The substantially perpendicular rod has a proximate end rigidly mounted to the exterior end of the principal brace bar outside of the housing, and a distal end, which extends outward, in a substantially perpendicular fashion, from the principal brace bar. Finally, the apparatus comprises a slideable brace bar with at least one hole therein. The hole corresponds to the substantially perpendicular rod, allowing the slideable brace bar to be mounted on the substantially perpendicular rod, in such a manner that the substantially perpendicular rod slides through the hole therein.
The elongated principal brace bar, the substantially perpendicular rod and the slideable brace bar are operative, in combination, to brace the door in a partially open position, so as to prevent forced entry and home invasion through the door.
Advantageously, the door security apparatus may be mountable to a conventional door, such that the apparatus may be operative to brace the door in a partially open position, and the sliding of the substantially perpendicular rod through the hole in the slideable brace bar may be operative to allow movement of the door between a closed position and the partially open position, where the door is braced.
Advantageously, the apparatus may further comprise a receptacle dimensioned to receive an active end of the slideable brace bar, and operative to immobilize the slideable brace bar at a predetermined position. In this manner, when the door is opening, the substantially perpendicular rod may slide towards an interior of the premises through the hole in the slideable brace bar. Eventually, the door will reach a partially open position, where the proximate end of the substantially perpendicular rod reaches the slideable brace bar and the slideable brace bar abuts against the principal vertical brace bar, thereby bracing the door in the partially open position. When the door is closing, the substantially perpendicular rod may slide away from the interior of the premises through the hole in the slideable brace bar. Eventually the door will come to a rest in a fully closed position when the slideable brace bar approaches the distal end of the substantially perpendicular rod.